The present invention relates generally to lighting controllers and in particular to light dimming systems.
Wall-mounted light switches which include a dimmer, known as dimmer switches, have become increasingly popular, especially for applications where it is desirable to precisely control the light intensity in a particular room. Such dimmer switches usually employ a variable resistor which is manipulated by hand to control the switching of a triac which in turn varies the voltage to the lamp to be dimmed.
This type of dimmer switch is simple and easy to construct, but offers limited flexibility. One feature this type of dimmer switch lacks is the ability to return to a preselected light intensity level after having been adjusted to a different light intensity. This type of dimmer switch has no memory to enable it to do this and preselected light intensity levels can be reestablished only by trial and error in manipulating the variable resistor.
There exist touch actuator controls which address some of the limitations of the manually-operated variable resistor controlled dimmer switches just described. One such touch actuator control cycles repetitively through a range of intensities from dim to bright in response to extended touch inputs. A memory function is provided such that, when the touch input is removed, the cycle will be stopped and the level of light intensity at that point in the cycle will be stored in a memory. A subsequent short touch input will turn the light off, and a further short touch input will turn the light on at the intensity level stored in the memory. While this type of switch is an improvement over manually-operated variable resistor controlled dimmer switches, it requires the user to go through the cycle of intensity levels in order to arrive at a desired intensity level. In addition, it still lacks the ability to return to a desired intensity level after having been adjusted to a different light intensity. A user must go through the cycle again until he or she finds the light intensity level desired. Moreover, this type of switch has no ability to perform certain aesthetic effects such as a gradual fade from one light intensity level to another.
U.S. Pat. No. 4,649,323 discloses a microcomputer-controlled light control which provides a fade function. The control disclosed in that patent is operated by a pair of switches which provide inputs to a microcomputer. The microcomputer is programmed to determine whether the switches are tapped or held (i.e., whether they are operated for a transitory duration or for a longer period of time). When a switch is held, the light intensity is either decreased or increased, depending on the switch operated, and release of the switch causes the intensity setting to be entered into a memory. If the control is operating at a static light intensity level, a tap of a switch will cause the light intensity level to fade toward a predetermined level, either off, full on or a preset level. A tap while the light intensity level is fading will cause the fade to be terminated and cause the light intensity level to shift immediately and abruptly to either full on or full off, depending on which switch was tapped. This type of control, however, is not without drawbacks. For example, a single tap of a switch by a user is interpreted in either of two very different ways (initiate fade or terminate fade), depending on the state of the control at the time the user applies the tap to a switch. This can be confusing to a user, who may erroneously terminate a fade when it is desired to initiate a fade, and vice versa. In addition, it is not possible to reverse a fade by a subsequent tap of the same switch while a fade is in progress. Instead, a tap while the control is fading in one direction will not reverse the direction of the fade but will cause the control to xe2x80x9cjumpxe2x80x9d to either full on or full off. An abrupt shift from a low intensity level to full on, or from a high intensity to no light at all (full off) can be quite startling to the user and others in the area (and even dangerous, if the user and others are suddenly plunged into darkness).
Commonly assigned U.S. Pat. Nos. 4,575,660; 4,924,151; 5,191,265; 5,248,919; 5,430,356 and 5,463,286 disclose various lighting control systems in which lamps or groups of lamps, in one or more zones, are varied in intensity to produce several different scenes of illumination. The level of intensity of the lamps constituting each lighting group is displayed to the user by either the number of light emitting diodes, LED""s illuminated in a linear array of the LED""s, or the position of a potentiometer slider in a linear track.
U.S. Pat. Nos. 5,191,265 and 5,463,286 disclose wall mounted programmable modular control systems for controlling groups of lights in one or more zones. In these systems, the lights are controlled by a master control wall module, a remote wall unit, and by a remote hand held control unit. The hand held unit communicates to the master control module by conventional infra-red (IR) transmission techniques.
The lighting control device disclosed in the U.S. Pat. No. 5,248,919 has all of the light control features needed to effectively and safely control the state and intensity level of one or more lights. However, this device lacks many desirable features such as wireless remote controllability, programmability, the ability to lock and unlock a preset, a delayed off, and the ability to store multiple presets. In many cases, it is desirable for a user to be able to have one or more lamps fade to a pre-selected intensity level or state, or to fade to off after a variable delay time. The lighting controls disclosed in the U.S. Pat. No. 5,248,919 are programmed to fade on to the last light level the dimmer was adjusted to prior to being turned off. This presents a problem because every time the light level of the dimmer is adjusted, the preset light level is changed. The user does not have the ability to lock in a light level that can be recalled when the unit is turned on after previously being turned off. It would be useful and desirable to be able to remotely control and program the preset light intensities of one or more lamps associated with one or more lighting scenes.
U.S. patent application Ser. No. 08/614,712 (now U.S. Pat. No. 5,909,087, which is assigned to the assignee of the present invention, and which is incorporated herein by reference, discloses a wallbox dimmer that can be programmed to store multiple preset levels. The infrared-handheld transmitter is manipulated to send infrared signals to the dimmer/receiver to enter a special programming mode. Once in programming mode, the user actuates a scene selector on the transmitter and then adjusts the light level by actuating a raise or a lower actuator on the dimmer/receiver or on the transmitter. The scene level is stored in the dimmer only when another scene select actuator is actuated or programming mode is exited. There is no way to store scene levels in the dimmer without using the transmitter and further there is no way to copy a scene preset from one actuator to another.
U.S. patent application Ser. No. 08/614,712 (now U.S. Pat. No. 5,909,087) further discloses the ability to lock and unlock a single preset light level into memory. With a preset light level locked into memory, when the dimmer is turned on, the dimmer goes to the light level locked in to the memory, and not to the last light level the dimmer was adjusted to prior to being turned off. The method for locking a preset light level into memory involves adjusting the dimmer to a desired light level using an intensity selector and then actuating a separate actuator three times in a short period of time (xc2xd second) to lock the level as a preset. Only one preset can be locked into memory. The patent application (now U.S. Pat. No. 5,909,087) further discloses a method for unlocking the preset. To unlock the preset, the user actuates the separate actuator four times in a short period of time (xc2xd second). When the preset is unlocked, the dimmer works like the dimmer disclosed in the U.S. Pat. No. 5,248,919, when it is turned off and then back on again.
Another lighting control device known in the art as xe2x80x9cOnset Dimmer OS600xe2x80x9d is manufactured by Lightolier Controls, Inc. The Lightolier device uses a separate dedicated switch in order to lock in a single preset light intensity level.
U.S. Pat No. 5,821,704, assigned to The Genlyte Group Incorporated, discloses a lighting control and dimming system that utilizes a single line voltage conductor for transmitting analog signals corresponding to a particular light intensity level of dimmers DIM 1, DIM 2, . . . DIM N in a dimmer group. Remote signaling and selection of a specific scene are performed independently of the phase of the applied AC line voltage by sampling the logic values of logic high to logic low and logic low to logic high transitions of a zero cross signal. Dimmers enabled by the transmitted analog signal produce a predetermined scene at a particular brightness level corresponding with one of the stored binary numbers.
The MULTISET family of dimmers and master control is available from Lightolier Controls Inc., a subsidiary of the assignee of the ""704 patent. The system consists of wallbox dimmers and a master control. The wallbox dimmers are each connected directly to a load. The user can access up to four presets plus xe2x80x9cfull onxe2x80x9d and xe2x80x9coffxe2x80x9d from the master control. The master control is capable sending preset signals over a single line voltage conductor to a maximum of 30 devices. To store a preset value in each dimmer, the user actuates a scene preset button on the master control, which causes all dimmers to go to their preset light level for that scene, and then adjusts the light intensity of the connected load at each of the dimmers, and then presses a very small dedicated xe2x80x9cstorexe2x80x9d actuator on each dimmer. The process of storing preset values is time consuming and requires a pin or other small device in order to access the store button. The only function of the store button is to store a light level as a preset, the store button can not be used to recall a preset. The master control is not capable of directly controlling an attached load.
The SCENE SELECT lighting control is available from Leviton Manufacturing Co. Inc. and is made up of Scene Dimmers and Scene Masters. The Scene Dimmer is a four scenes and off wallbox dimmer that can be connected directly to a load. Each of the four scenes is programmable by the user. The loads can be lighting loads or fan loads. A Scene Dimmer can be used independently to control an associated load or as part of a system with a Scene Master control.
In order to save a level as a preset with the Scene Select lighting control, the faceplate for the lighting control must first be removed. Hence it is impossible for the user to change a preset or scene value after the lighting control is installed without taking the faceplate off. Scenes and presets are herein used interchangeably. To program a scene, the user must press and hold the scene actuator to be programmed, press and hold a xe2x80x9ccyclexe2x80x9d actuator until the desired light intensity is reached, release the xe2x80x9ccyclexe2x80x9d button, and then release the scene actuator. When the xe2x80x9ccyclexe2x80x9d actuator is held the light output from the dimmer continuously cycles up and down until the actuator is released as described above. With only one button to cause the light level to increase or decrease, this makes it very difficult to make small adjustments to the light intensity. If the user just misses the light level needed, the user must go through the entire cycle and hope to catch it the next time through. The preset light levels are stored in the individual dimmers and not in the master control.
The Scene Master is used to signal Scene Dimmers to fade to their respective scenes. The Scene Master communicates to the Scene Dimmers over a single line voltage conductor. The programming of a scene in a system is the same as with an individual dimmer, but it must be done independently for each dimmer in the system. This can be a very time consuming process when there are multiple dimmers. The Scene Master is not used during the storing process.
Another product available from Leviton Manufacturing Co. Inc. is a four preset wall box dimmer that is not user adjustable. The four presets are set at the factory and cannot be changed by the user.
In one prior art system, a user can add a so-called three-way switch, i.e., an additional light control switch, to an existing hard wired single control system by replacing an existing manually operated lighting control device with a lighting control device having a radio frequency receiver incorporated therein. The replacement lighting control device is hard wired into the electrical system in the same way as the conventional device to control a lamp in a lighting fixture. The radio frequency receiver is responsive to radio frequency signals generated by a remote battery powered switching device having a transmitter which can be conveniently affixed to a building wall at another location, thereby to provide the three-way switch circuit. The additional battery powered lighting control device has a manually operated lever, which when operated, sends an RF signal to the other electrical control device which is hard wired into the building""s electrical system. The hard wired device will then toggle in response from its present state to the opposite state, i.e., from on to off or off to on. Thus, either switching device, the hard wired replacement or the battery powered device, can operate the lamp. Accordingly, a three-way switch can be provided to an existing electrical system without hard wiring the three-way switch into the system. In this prior art system, having the battery powered transmitting switch and the hard wired switch including the receiver, the hard wired receiving switch includes a whip antenna made from a piece of insulated wire which may be allowed to dangle out of the electrical box either outside the building wall or inside the wall. The receiver in the hard wired switch allows only one way communication i.e., it receives signals from the battery powered transmitting switch. Two-way communication between the hard wired switch and the transmitting switch is not provided. A system of this type is sold by Heath Zenith as the Reflex switch. Another device of this type, which instead employs a hand-held remote control to provide a three way switching function, is manufactured by Dimango.
In another prior art system an existing hard wired manually operated lighting control device is replaced with a lighting control device having a radio frequency receiver incorporated therein. The replacement lighting control device is hard wired into the electrical system in the same way as the conventional device to control the lamp in a lighting fixture. The radio frequency receiver is responsive to radio frequency signals generated by a remote battery powered control device having a transmitter which can be conveniently affixed to a building wall at another location. The battery powered control device has switches to enable the selection of four different light levels. The switches when operated cause an RF signal to be sent to the electrical control device which is hard wired into the building""s electrical system. The hard wired device responds to the RF signals by adjusting its output to cause the lamp to operate at one of four different predetermined light levels. In addition to responding to RF signals, the hard wired device can also operate in response to the actuation of manually actuated switches incorporated within it. Two way communication between the hard wired device and the battery powered control device is not provided. A system of this type is sold by Leviton as the Anywhere switch.
Thus there is a need for an improved lighting control and dimming device which offers advantages not possible with prior controls while avoiding the drawbacks of the prior controls. The present invention fills that need.
This invention relates to a lighting control system capable of storing and recalling multiple preset light levels. The method for storing the presets is simple and straight forward. To save a preset light level, the user simply adjusts a dimmer, using a user adjustable intensity selector, to the desired light level and then presses and holds a preset actuator for a non transitory period of time, preferably greater than 1 second, more preferably greater than 3 seconds. To recall the preset light level the user simply actuates the preset actuator, preferably for a transitory period of time, preferably less than 1 second, more preferably less than xc2xd second. The preset actuator can be mounted in a common housing with the user adjustable intensity selector or a separate housing. When the user adjustable intensity selector and the preset actuator are mounted in a common housing, preferably the user adjustable intensity selector is spaced from the preset actuator by no less than 1xe2x80x3.
The present invention also relates to a lighting control system capable of communicating from a master control to a dimmer without the need for additional wiring. The master communicates with the dimmer preferably through infrared energy within the wallbox. An infrared transmitting diode located within the master control directs the infrared energy out of the master for receipt by the dimmers.
The present invention also relates to a lighting control system capable of communicating from a master control located in a first wallbox to a dimmer located in a second wallbox. The master communicates to the dimmer preferably through signals transmitted through a flexible conductor. In a first preferred embodiment, the signals are infrared signals conducted through an infrared conductive cable such as a hollow flexible tube or a fiber optic cable. In a second preferred embodiment an infrared transmitting diode is located at an end of an electric cable, the other end being connected to the master control. The cable can be easily routed from the first wallbox to the second wallbox.